SCSI RAID card recommendation (1/2 height PCI-X U320 SCSI dual channel)

[Chuck Swiger]

Vivek Khera wrote:
[ ... ]
> The only other aac controller I have is a Dell PERC type which is god- 
> awful slow, but I hear that's dell's fault not adaptec's.  I don't  know 
> what to believe there.  That card is quite stable however.
> 
> Any experiences with this that anyone wishes to share?

There's an interesting thread about the AMR RAID controller used in the newer 
18x0/28x0 Dells with the PERC/4 controller, and I know of enough people using 
them that such improvements (by Doug Ambrisko?) will be welcomed.

If you've got the older PERC/3 AAC controller, it looks something like this:

6-pi# dmesg | grep aac
aac0: <Dell PERC 3/Di> mem 0xf0000000-0xf7ffffff irq 31 at device 2.1 on pci2
aac0: i960RX 100MHz, 118MB cache memory, optional battery present
aac0: Kernel 2.5-0, Build 2991, S/N xxxxx
aac0: Supported Options=0
aacd0: <RAID 1 (Mirror)> on aac0
aacd0: 17355MB (35544576 sectors)
Mounting root from ufs:/dev/aacd0s1a
7-pi# diskinfo -v -t aacd0
aacd0
         512             # sectorsize
         18198822912     # mediasize in bytes (17G)
         35544576        # mediasize in sectors
         2212            # Cylinders according to firmware.
         255             # Heads according to firmware.
         63              # Sectors according to firmware.

Seek times:
         Full stroke:      250 iter in   1.344172 sec =    5.377 msec
         Half stroke:      250 iter in   1.300260 sec =    5.201 msec
         Quarter stroke:   500 iter in   2.705104 sec =    5.410 msec
         Short forward:    400 iter in   2.605101 sec =    6.513 msec
         Short backward:   400 iter in   2.157570 sec =    5.394 msec
         Seq outer:       2048 iter in   0.954848 sec =    0.466 msec
         Seq inner:       2048 iter in   0.952256 sec =    0.465 msec
Transfer rates:
         outside:       102400 kbytes in   3.248853 sec =    31519 kbytes/sec
         middle:        102400 kbytes in   3.174779 sec =    32254 kbytes/sec
         inside:        102400 kbytes in   4.612511 sec =    22200 kbytes/sec

8-pi# uname -a
FreeBSD pi.codefab.com 5.4-STABLE FreeBSD 5.4-STABLE #0: Wed Nov  9 23:04:08 EST
  2005     root at pi.codefab.com:/usr/obj/usr/src/sys/PI  i386

...set up as a RAID-1 mirror using a pair of 18 GB, hmm, 10K RPM Seagates, IIRC?
Seems a bit slower under 5 than under 4, but not unreasonably so.

-- 
-Chuck